For example, when a system having, for example, plural servers receives a request from a client, messages are exchanged between the servers, as depicted in FIG. 13, to advance the processing. Incidentally, FIG. 13 depicts the system including a Web server, an application (APL) server, and a database (DB) server. Furthermore, a sequence of the messages exchanged between the servers is different according to the request from the client, for example.
For example, when there is a message including, as a parameter, an employee number, this message has the same number of variations as the number of employees. However, an analyst who analyzes the system may want to handle such variations of the message as one kind of message. In order to resolve such a problem, there is a technique (e.g. Japanese laid-open patent publication No. 2006-236280) to convert the grain size of the message according to a predefined conversion rule. According to such a technique, it is possible to convert the messages so as to leave only a required portion, and it is also possible to appropriately judge the identity of the messages.
However, there are variations in a search formula by, for example, Structured Query Language, and the search formula may vary for each job. Therefore, it is very difficult for a person to manually prepare rules to convert the grain size of the database messages including an SQL sentence. Incidentally, there is no conventional technique to automatically generate rules to convert the grain size of the database messages.